Titanium or zirconium lining structure



SePt- 15, 1954 AsAHlKo GoTo TITANIUM 0R zxRcoNTUM LIN'ING STRUCTUREFiled Jan. 17, 1961 FGTB Inventor AJA/#Ko GOTO A Homey United StatesPatent() 3,148,953 'IlTANlUM @R ZllCNUM LINING STRUCTURE Asko Goto,Nada-ku, Kobe, Japan, assigner to Kobe Steel Works, Ltd., Kobe, JapmlFiled lan. 17, 1961, Ser. No. $3,259 Claims priority, application JapanAug. 19, 196? 1 Qlaiin. (Cl. 29-191) The present invention relates to atitanium or zirconium lining structure. More particularly, the presentinvention relates to mounting a titanium or zirconium liner inside abody made of another metal.

It should be understood that the term titanium or zirconium as used inthe specification and claims is intended to mean not only pure titaniumor zirconium respectively but also titanium base alloys or zirconiumbase alloys respectively. lt should also be understood that a body towhich the titanium or zirconium liner is to be mounted according to thisinvention refers to any equipment made of a metal (such as soft steel,stainless steel) other than titanium and zirconium. Typical examples ofsuch body are distillation towers, columns, reaction vessels, tanks andthe like which are employed in the field of petrolio chemical and otherchemical industries and various huid transportation and storage andwhich are desired to be rendered corrosion resistant by means of aliner.

Titanium, zirconium and their alloys are Well known to be excellent incorrosion resistant property, so that they have been used in themanufacture of various parts, articles and equipments, such asdistillation columns for the purification of petroleum and variouschemical reaction vessels and apparatus which are required to beanti-corrosive. However, this proposal has encountered difficulties inthat titanium, zirconium and their base alloys are costly as comparedwith other conventional metals such as stainless steel, and are notreadily weldable to other metals.

lt has been proposed, therefore, to mount a titanium or zirconuim linerinside bodies such as reaction towers or distillation columns made ofanother metal such as soft steel or stainless steel. However, thisproposal has not fully been successful because titanium and zirconium donot lend themselves to welding. This drawback is particularly notablewhen a liner is to be applied locally or partly only on a portion of thebody where corrosion esistance is particularly desired. Furthermore,there has been another diiculty that those portions of the liner whichare not welded or are not weldable to the body are distended from theinner Wall toward the interior of the body (vessel, column and the like)when it is subjected to negative pressure.

Therefore, where it is desired to locally mount a liner only on the areawhere corrosion is particularly noticeable, it has been inevitable toinsert a foil or leaf of silver, silver-manganese or the like betweenthe wall (stainless steel, soft steel, etc.) and the liner and then tosubject the assembly to seam welding. This operation, however, is verytroublesome and diilicult, particularly when the diameter of the bodysuch as vessel, column is relatively large. When the body is to beemployed in the applications where it is subjected to a negativepressure, it has been necessary to fasten the zirconium or titaniumliner to the body wall by means of a number of titanium (or zirconium)locking or set screws or the like and then to edge arc-weld the head ofeach of the screws to the Wall. However, according to this procedure,the number and pitch w aitaasa Patented Sept. l, 1964 of the screwsrequired depends upon the thickness of the liner and the vacuum degreeto which the vessel or column is subjected. It is very diflicult todetermine the number of the srcews and the pitch of the arrangementofthe screws. Thus, sometimes it is excessive so that the apparatusbecomes unduly expensive, and sometimes it is less than actuallyrequired so that the liner is unstable under'the negative pressure.Furthermore, due tothe use of a number of screws the possibility ofleakage is increased and the life of the apparatus is shortened.

Therefore, it is an object of this invention to overcome all thesedrawbacks heretofore encountered in mounting a titanium or zirconiumliner to a body of another metal.

lt is another object of this invention to effectively mount a titaniumor zirconium liner to a body made of another metal, with a minimumnumber of screws or without such screws so as to avoid the possibilityof leakage and to lengthen the life of the body.

lt is still another object of this invention to mount a titanium orzirconium liner to a body made of another metal, in such a manner as toeffectively avoid a distention or displacement of the liner whensubjected to a negative pressure.

lt is still another object of this invention to provide a titanium orzirconium lining structure on a body made of another metal, said liningstructure being rigid and strong and not adversely affected by pressurevariation.

Finally, it is an object of this invention to provide a titanium orzirconium lining structure of the type men-v tioned above which can beeasily accomplished by a person who is not skilled in the art of highgrade welding or xing technique.

Brielly, the above and further objects of the invention.

are achieved by the utilization of a separate member and Without anydirect and face to face integral welding between the body and the liner.Thus, according to this invention, the liner is superposed at the endportion on the body wall together with a separate ring or annularmember, and the annular member and the liner end portion are xedtogether onto the body Wall by means of a screw, bolt or the like madeof titanium or zirconium. This screw or bolt is welded to the liner.According to a preferred embodiment of the invention the liner is formedwith a number of internally projected ribs or undulations at intervalslongitudinally of the liner for the purpose of reinforcement andprevention of an inward distention or displacement of the liner.Alternatively or additionally, for the same purposes, a number ofannular support members made of titanium or zirconium are welded on theliner at intervals longitudinally of the liner.

The invention, both as to the liner structure and method foraccomplishing the same, together with further objetcs and advantagesthereof, will best be understood from the following detailed descriptiontaken in connection with the accompanying drawings in which:

FlG. 1 is a longitudinal section of a part of a column or vessel bodywith a liner of this invention;

FlG. 2 is a view similar to FIG. 1 but showing another embodiment of theinvention; and

FlG. 3 is a view similar to FIG. l but showing still another embodimentof the invention and various additional features of the invention.

For convenience of explanation, in the following description a liner isdescribed as to be made of titanium,

3 coniurn, a titanium alloy or a zirconium alloy where the liner is madeof these materials respectively.

The structure shown in FIG. 1 is a particularly useful to mount a lineronly on a local area of a. column or vessel. Indicated with thereference numeral 1 is a column body Wall made of a soft steel orstainless steel. A titanium liner sheet 2 is placed along and in contactwith the inner surface of the wall 1 and its lower end portion 2 is bentand removed from contact with the inner surface of the wall 1 so as toform a gap therebetween, into which gap an upper end portion of aseparate annular or ring member 3 made of soft steel or stainless steelis inserted and tted. Preferably, the member 3 has a thicknessapproximately equal to that of the liner 2. Thus the lower end portion 2of the liner 2 and the upper end portion of the annular member 3 aresuperposed together on the inner surface of the wall 1. The annularmember 3 is placed along and in contact with the inner face of thewall 1. Through the superposed portions a set screw 4 made of titaniumis threaded into the wall 1 so as to bond them together. It will beunderstood that there exist a number of such screws 4 arranged atsuitable intervals along the inner periphery of the superposed portions.In FIG. l there appear four screws (one being in section). The head 4 ofeach of the screws 4 is arc welded to the liner and then brazed at 5.The lower edge of the liner 2 is brazed throughout its length at 6 tothe adjacent face of the ring member 3. It has been found .that asatisfactory result is obtained when this brazing is carried out byusing pure silver or a silver alloy. The lower edge of the ring member 3is welded throughout its length to the adjacent face of the wall 1 asshown at 7. Furthermore, the ring member 3 is bonded to the wall 1adjacent the superposed portion by means of a number of plug or spotwelds 8 at intervals along the inner periphery thereof.

The upper end portion of the liner 2 may be of the structure same asthat shown and described in respect of the lower end portion.

According to this lining structure, the liner is rigidly secured to thewall and is very stable. The brazed portion has a strength of 20-25kg./cm.2. Since the brazing or welding can be carried out easily andcompletely by an edge arc torch or twin arc torch there is required nohigh grade technique and care.

The embodiment shown in FIG. 2 is particularly eifective in thoseapplications where the lined body is exposed to a negative pressure. Atitanium liner 12 to be secured or mounted on the inner surface of thebody wall 11 is formed with a number of parallel inner periphery ribs orundulations 13 arranged at intervals longitudinally of the liner. Therib may have any suitable cross sectional shape. In the embodimentshown, it is a hollow semicircular shape in cross section. Here also,the wall 11 is made of soft steel or stainless steel. If desired, areinforcement annular member 14 having a suitable crosssectional shapesuch as channel shape as shown and made of titanium is welded at 15 ontoand along the periphery of the inner face of the liner 12 to obtainadditional reinforcement. 'Ihe number and position of the ring(s) 14 maybe determined in accordance with necessity.

The upper and lower end portions may be secured or bonded to the wall 11in the same manner as shown in FIG. 1. However when the liner 11 isconsiderably long, the liner becomes considerably heavy due to thelength and the provision of the ribs (and reinforcement rings, ifprovided). In such circumstances, and particularly when the apparatus issubjected to an extremely high negative pressure, the mounting structureshown in FIG. l may be not fully satisfactory. Therefore, it ispreferable to employ, at each end portion of the liner, a support ringmember 16 made of titanium. If desired, the ring member 16 is flanged asshown so that the flange may support a part (such as a filter, tray,etc.) of the apparatus, if any, within the body 11. The support ring 16also serves to prevent an inward displacement or distention of the 4liner 12 under negative pressure, and to secure the liner 12 to the wall11 as described below.

At each end portion of the titanium liner 12, a bolt 18 made of titaniumis threaded and fastened into the wall 11 through the liner 12. The bolt18 is Welded to the liner metal at 17 The ring 16 is mounted on thisbolt 18 through its opening and the assembly is tightened by means of acooperating nut 19 made of titanium. It is preferable to secure areinforcement plate 20 on the surface of the wall 11 opposite to thoseareas where the bolts 18 are extended. The plate 2t) is made of softsteel or stainless steel and is welded at 21 to the outer surface of thebody 11. It will be understood that there exist a desired number of suchbolts arranged at suitable intervals along the inner periphery of thesuperposed (wall, liner and support ring) portion.

By .this structure, a sufficient resistance of the liner to negativepressure is assured. The liner is rigidly and stably secured and is notadversely affected by a variation in vacuum degree within the vessel. Itis not necessary to employ a number of titanium screws or the like sothatk a troublesome operation is avoided. The operation to secure theliner is quite easy because only a simple welding operation is requiredin welding the bolts.

In some instances, it may be desired to avoid the use of a liner formedwith ribs or undulations. In the embodiment shown in FIG. 3,reinforcement ring or annular members are separately attached to theinside of the liner 12 instead of integrally forming the ribs thereon.

In this embodiment, each of the upper and lower end portions of thetitanium liner 12 is secured or bonded to the steel wall 11 in the samemanner as shown in FIG. 2. Between these ends, a number of parallelreinforcement rings are secured on and along the periphery face of theliner at intervals longitudinally of the liner. These reinforcement ringor annular members are made of titanium and are secured to the liner bymeans of welding. The ring or annular member may have various crosssectional shape.

The ring shown in FIG. 3a consists of two ring shaped plates assembledand secured to the line 12 by spot welding 23 so as to be a triangularshape in cross section. Along the ridge line the plates are spot weldedtogether at 23. Since the ring is spot Welded at intervals the interiorof the triangle ring is not comple-tely sealed or closed but cancommunicate with the interior of the vessel 1 so that the pressure isequalized.

In the embodiment shown in FIG. 3b the ring is L- shaped in crosssection, and the ring shown in FIG. 3c is rectangular in cross section.In each case, the ring is secured to the liner 12 by means of linewelding 24 along the edge adjacent the liner face throughout the length.

In still another embodiment shown in FIG. 3d, the ring is a circulartubular (circular in cross section) and is line welded at 24 throughoutthe length to the liner 11. In this case, it is preferable to provide asuitable number of small openings 25 on the tubular ring so as toequalize the interior pressure thereof with that of the vessel 11.

While some particular embodiments of the invention have been shown anddescribed it will be recognized that various modifications will readilyoccur to those skilled in the art and it is therefore contemplated bythe appended claim to cover any such modifications as fall within thespirit and scope ofthe invention.

What I claim is:

A hollow body structure, comprising, in combination:

(a) a hollow body of a ferrous material;

(b) a liner of a material selected from the group consisting of titaniumand zirconium;

(c) a support ring member, said liner being superposed on the innersurface of a wall of said body with said support ring member;

(d) a separate ring member of a ferrous material, the

end portions of said liner being superposed on an end portion of saidseparate ring member with the end portion of said liner spaced from saidWall and References Cited in the le of this patent said separate ringmember contacting said wall; UNITED STATES PATENTS (e) set screws of amaterial selected from the group consisting of titanium and zirconium,said set screws 4392266 Seme- --f APL 6, 1943 securing the superposedportions to said body wall; 5

and OTHER REFERENCES (f) weld means bonding said separate ring member t0The Welding Journal, Fabrication of a Zirconiumsaid body Wall andproviding a connection at the Lined RaCOll Vessel, Febllaf/ 1954, PP-115-118- junction of the end portion of said liner and said separatering member. 10

